Process for the manufacture of water-clear copolymer dispersions

Abstract

Copolymer dispersions can be prepared by emulsion polymerization of mixtures of unsaturated carboxylic acids and the esters thereof in the presence of regulators. Using sulfur containing compounds as regulators odorless and colorless dispersions which do not discolor are obtained if mercapto compounds having at least two SH-groups are used as regulator and the dispersions after polymerization are treated with hydrogen peroxide. The dispersions are especially suitable as film forming component in dry bright emulsions for the care of floors.

What is claimed is: 
     
       1. A process for the manufacture of an odorless and colorless aqueous copolymer dispersion which can be rendered water-clear by the addition of ammonia and does not discolor by polymerizing acrylates, methacrylates, unsaturated acids and optionally a small amount of styrene in the presence of a mercapto compound as regulator, which comprises a. polymerizing the monomers in the presence of from 0.1 to 5.0 % by weight, calculated on the weight of the monomers, of a mercapto compound having at least 2 SH groups in the molecule as regulator and   b. incorporating into the copolymer dispersion of from 0.1 to 5.0 % of hydrogen peroxide, calculated as H 2  O 2  of 100 % strength on the weight of the monomers, at a temperature of from 60° to 95° C after completion of the polymerization.   
     
     
       2. The process as claimed in claim 1, wherein the mercapto compound having at least 2 SH groups in the molecule used as regulator is a thioglycol, thio-glycerol, thio-pentaerythritol, or an ester of a saturated polyhydric aliphatic alcohol having from 2 to 6 carbon atoms with a saturated aliphatic mercapto monocarboxylic acid having from 2 to 6 carbon atoms.